A novel pH-responsive electrochemiluminescence immunosensor for ALV-J detection based on hollow MnO2 encapsulating Ru(bpy)3Cl2

Manganese-derived biomaterials for tumor diagnosis and therapy

Manganese (Mn) is widely recognized owing to its low cost, non-toxic nature, and versatile oxidation states, leading to the emergence of various Mn-based nanomaterials with applications across diverse fields, particularly in tumor diagnosis and therapy. Systematic reviews specifically addressing the tumor diagnosis and therapy aspects of Mn-derived biomaterials are lacking. This review comprehensively explores the physicochemical characteristics and synthesis methods of Mn-derived biomaterials, emphasizing their role in tumor diagnostics, including magnetic resonance imaging, photoacoustic and photothermal imaging, ultrasound imaging, multimodal imaging, and biodetection. Moreover, the advantages of Mn-based materials in tumor treatment applications are discussed, including drug delivery, tumor microenvironment regulation, synergistic photothermal, photodynamic, and chemodynamic therapies, tumor immunotherapy, and imaging-guided therapy. The review concludes by providing insights into the current landscape and future directions for Mn-driven advancements in the field, serving as a comprehensive resource for researchers and clinicians.

Hollow Mesoporous Manganese Oxides: Application in Cancer Diagnosis and Therapy

The precision, minimal invasiveness, and integration of diagnosis and treatment are critical factors for tumor treatment at the present. Although nanomedicine has shown the potential in tumor precision treatment, nanocarriers with high efficiency, excellent targeting, controlled release, and good biocompatibility still need to be further explored. Hollow mesoporous manganese oxides nanomaterials (HM-MONs), as an efficient drug delivery carrier, have attracted substantial attention in applications of tumor diagnosis and therapy due to their unique properties, such as tumor microenvironment stimuli-responsiveness, prominent catalytic activity, excellent biodegradation, and outstanding magnetic resonance imaging ability. The HM-MONs can not only enhance the therapeutic efficiency but also realize multimodal diagnosis of tumors. Consequently, it is necessary to introduce applications based on HM-MONs in cancer diagnosis and therapy. In this review, the representative progress of HM-MONs in synthesis is discussed. Then, several promising applications in drug delivery, bio-imaging, and bio-detection are highlighted. Finally, the challenges and perspectives of the anticancer applications are summarized, which is expected to provide meaningful guidance on further research.

Ultrasensitive electrochemiluminescence sensor based on perovskite quantum dots coated with molecularly imprinted polymer for prometryn determination

A highly effective molecularly imprinted electrochemiluminescence sensor was constructed for prometryn determination in environmental and biological samples by using perovskite quantum dots coated with a molecularly imprinted silica layer (MIP/CsPbBr₃-QDs) as the recognition and response element. MIP/CsPbBr₃-QDs were immobilized on a glassy carbon electrode (GCE) through electropolymerization, and the electrochemiluminescence (ECL) response of MIP/CsPbBr₃-QDs could be motivated under the condition of H₂O₂ as co-reactant. ECL signal was selectively quenched with prometryn by hindering electron transfer and directly proportional to the logarithm of prometryn concentration (0.10-500.0 μg/L) with a correlation coefficient of 0.9960. Limits of detection in fish and seawater samples were 0.010 μg/kg and 0.050 μg/L, respectively. Excellent recoveries of 88.0%-106.0% were acquired for fish and seawater samples with a relative standard deviation below 4.2%. The constructed MIECL sensor based on MIP/CsPbBr₃-QDs showed good stability, accuracy, and precision for sensitive detection of prometryn in aquaculture products and environmental samples.

Ratiometric fluorescence immunoassay based on MnO2–o-phenylenediamine–fluorescent carbon nanodots for the detection of α-fetoprotein via fluorescence resonance energy transfer

The ratiometric fluorescence immunoassay based on MnO2–o-phenylenediamine–fluorescent carbon nanodots is superior to the traditional single-wavelength-based method.

Ultrasensitive bioassaying of HER-2 protein for diagnosis of breast cancer using reduced graphene oxide/chitosan as nanobiocompatible platform

Background

In this label-free bioassay, an electrochemiluminescence (ECL) immunosensor was developed for the quantification of breast cancer using HER-2 protein as a metastatic biomarker.

Method

For this purpose, the ECL emitter, [Ru(bpy)3]2+, was embedded into biocompatible chitosan (CS) polymer. The prepared bio-composite offered high ECL reading due to the depletion of human epidermal growth factor receptor 2 (HER-2) protein. Reduced graphene oxide (rGO) was used as substrate to increase signal stability and achieve greater sensitivity. For this, rGO was initially placed electrochemically on the glassy carbon electrode (GCE) surface by cyclic voltammetry (CV) technique. Next, the prepared CS/[Ru(bpy)3]2+ biopolymer solution was coated on a drop of the modified electrode such that the amine groups of CS and the carboxylic groups of rGO could covalently interact. Using EDC/NHS chemistry, monoclonal antibodies (Abs) of HER-2 were linked to CS/[Ru(bpy)3]2+/rGO/GCE via amide bonds between the carboxylic groups of Ab molecules and amine groups of CS. The electrochemical behavior of the electrode was studied using different electrochemical techniques such as electrochemical impedance spectroscopy (EIS), differential pulse voltammetry (DPV) and square wave voltammetry (SWV) and also ECL tests.

Results

After passing all optimization steps, the lower limit of detection (LLOQ) and linear dynamic range (LDR) of HER-2 protein were practically obtained as 1 fM and 1 fM to 1 nM, individually. Importantly, the within and between laboratory precisions were performed and the suitable relative standard deviations (RSDs) were recorded as 3.1 and 3.5%, respectively.

Conclusions

As a proof of concept, the designed immunosensor was desirably applied for the quantification of HER-2 protein in breast cancer suffering patients. As a result, the designed ECL-based immunosensor has the capability of being used as a conventional test method in biomedical laboratories for early detection of HER-2 protein in biological fluids.

Graphic Abstract

A novel site-induced biomolecule anchoring strategy based on solid superacid ZrO2/SO42- for fabricating label-free IgG electrochemical immunosensors

In this work, a unique zirconium dioxide solid superacid (ZrO₂/SO₄²⁻) was utilized for the fabrication of an IgG electrochemical immunosensor.

The antiviral property of Sargassum fusiforme polysaccharide for avian leukosis virus subgroup J in vitro and in vivo

Avian Leukosis Virus Subgroup J (ALV-J) is an oncogenic retrovirus, mainly spread by vertical and horizontal transmission, which have caused severe losses in world poultry industry. Sargassum fusiforme polysaccharide (SFP), a marine algae sulfated polysaccharide, has attracted more attention due to its variously biological activities. In this study, the anti-ALV-J property of SFP was assessed in vivo and in vitro. The results demonstrated that different Mw of SFPs showed virustatic activity to ALV-J in vitro by combining with the virus when ALV-J adsorbed onto the host cells. When treated with SFPs, the ALV-J gene and protein expression reduced clearly and SFP-3 (Molecular weight 9 kDa) had the best antiviral effect. Results in vivo showed that the immunosuppression of the ALV-J infected chickens were relieved by SFP-3. Moreover, SFP-3 obviously inhibit the viral shedding and alleviated the organs damage caused by ALV-J. This study offered a new method for ALV-J treatment and enriched the potential application of SFP.

Highly sensitive bioaffinity electrochemiluminescence sensors: Recent advances and future directions

Electrogenerated chemiluminescence (also called electrochemiluminescence and abbreviated ECL) has attracted much attention in various fields of analysis due to the potential remarkably high sensitivity, extremely wide dynamic range and excellent controllability. Electrochemiluminescence biosensor, by taking the advantage of the selectivity of the biological recognition elements and the high sensitivity of ECL technique was applied as a powerful analytical device for ultrasensitive detection of biomolecule. In this review, we summarize the latest sensing applications of ECL bioanalysis in the field of bio affinity ECL sensors including aptasensors, immunoassays and DNA analysis, cytosensor, molecularly imprinted sensors, ECL resonance energy transfer and ratiometric biosensors and give future perspectives for new developments in ECL analytical technology. Furthermore, the results herein discussed would demonstrate that the use of nanomaterials with unique chemical and physical properties in the ECL biosensing systems is one of the most interesting research lines for the development of ultrasensitive electrochemiluminescence biosensors. In addition, ECL based sensing assays for clinical samples analysis and medical diagnostics and developing of immunosensors, aptasensors and cytosensor for this purpose is also highlighted.

Au@Pt nanodendrites enhanced multimodal enzyme-linked immunosorbent assay

Single modal enzyme-linked immunosorbent assay (ELISA) covering colorimetric, fluorescence, and chemiluminescence techniques has been widely reported in recent years, whereas the combination of multiple signal channels in one immunosensing platform still faces huge challenges. Multimodal imaging will provide more comprehensive and precise diagnostic information by the combination of two or more imaging modalities. Inspired by this concept, we established a new kind of multimodal enzyme-linked immunosorbent assay (M-ELISA) based on the unique properties of Au@Pt nanodendrites. As a proof-of-concept demonstration, cardiac troponin I (cTnI) has been chosen as a model biomarker. Owing to the excellent photothermal effect and intrinsic peroxidase-like activity of Au@Pt nanodendrites, the concentration of cTnI can be quantificationally reflected by photothermal immunoassay, colorimetric immunoassay and ratiometric fluorescence immunoassay simultaneously. This developed M-ELISA demonstrated the good consistency with the chemiluminescence immunoassay method in clinical diagnosis for real serum samples.